In Norse mythology, Odin is the supreme god. His role, like many of the Norse pantheon, is complex: he is both god of wisdom and war, roles not necessarily conceived of as being mutually sympathetic in contemporary society. His name has roots in the old Norse word örðr, meaning "inspiration, madness, anger".

His name, for the warlike Norsemen, was synonymous with battle and warfare, for it recurs throughout the myths as the bringer of victory. Odin was a shape-changer, able to change his skin and form in any way he liked. He was said to travel the world disguised as an old man with a staff, one-eyed, grey-bearded and wearing a wide-brimmed hat (called Odin Gangleri ("the wanderer").

He was married to the goddess Frigg, who appears in the myths mainly as a dutiful wife and loving mother (of Beldegg or Tyr?). With Frigg, he was the father of Bragi, Balder, Hod, Hermod and Thor (sometimes, Thor's mother was Jord instead). With Grid, he was the father of Vidar. He was a son of Bestla and Bor and brother of Ve and Vili, with whom he created humanity (see Ask and Embla). He possessed Sleipnir, an eight-legged horse, and the severed head of the dwarf Mimir, which foretold the future. He employed Valkyries to gather the souls of warriors fallen in battle (the Einherjar), as these would be needed to fight for him in the battle of Ragnarok. Originally, the Valkyries appear to have been viewed as vampire-like ghouls who frequented battlefields to drink the blood of the slain, but by the time Scandinavia emerged into written history, they appeared as aristocratic maidens in the service of Odin. They took the souls of the warriors to Valhalla (the hall of the fallen), Odin's residence in Asgard. Every evening these spirits, the einherjar, feasted on a piece of Odin's body and were reborn after a day of heavy training in which they cut each other to pieces. One of the Valkyries, Brünnehilde, was imprisoned in a ring of fire by Odin for daring to disobey him. She was rescued by Sigurd. He was similarly harsh on Hod, a blind god who had accidentally killed his brother, Baldur. Odin and Rind, a giantess, birthed a child named Vali for the specific purpose of killing Hod.

Odin was a compulsive seeker of wisdom, consumed by his passion for knowledge, to the extent that he sacrificed one eye and also hung himself from the tree Yggdrasil, whilst pierced by his own spear, to acquire knowledge. He hung there for nine days and nights, a number deeply significant in Norse magical practice (there were, for example, 9 realms of existence), thereby learning nine magical songs and eighteen magical runes. The purpose of this strange ritual, a god sacrificing himself to himself because there was nothing higher to sacrifice to, was to obtain mystical insight through mortification of the flesh; however, some scholars assert that the Norse believed that insight into the runes could only be truly attained in death. Odin's love for wisdom can also be seen in his work as a farmhand for a summer, for Baugi, in order to obtain the mead of poetry. See Fjalar and Galar for more details.

Some scholars would see this as a garbled version of the story of Christ's crucifixion, but perhaps it is more likely that the poem shows the influence of shamanism, where the symbolic climbing of a "world tree" by the shaman in search of mystic knowledge is a common religious pattern. We know that sacrifices, human or otherwise, to the gods were commonly hung in or from trees, often transfixed by spears. Incidentally, one of Odin's alternative names is Ygg, and Yggdrasil therefore means "Ygg's (Odin's)horse". Another of Odin's names is Hanga, the god of the hanged.

The creation of the runes, the Norse alphabet that was also used for divination, is attributed to Odin and is described in the Havamal, part of the Poetic Edda.

Odin has a number of magical artifacts associated with him: the dwarven spear Gungnir, a magical gold ring (Draupnir), an eight-legged horse (Sleipnir), and two ravens Hugin and Munin (Thought and Memory) who travel the world to acquire information at his behest. He also commands a pair of wolves named Geri and Freki. From his throne, Hildskjalf[?] (located in Valaskjalf[?]), Odin could see everything that occurred in the universe.

Snorri Sturlusson's Edda depicts Odin as welcoming into his hall, Valhalla, the courageous battle-slain. These fallen, the einjehar, will support Odin at the final battle of the end of the world, Ragnarok.

Odin (Óðinn) is also referred to as Vóden. Other variations are: Othinn; Old High German Wuotan; Old Low German Wodan, Wotan; and Old English Woden. The Old English version, Woden, appears to mean "furious", "wild", "mad". The god is believed to be manifest in a noisy, bellowing movement across the sky, not unlike Vâta, Lord of Wind of the Hindu. It is unsurprising therefore to find Odin deeply associated with the concept of the Wild Hunt, called in Norse beliefs Asgardareid. Odin and Frigg participated in this together. Odin sometimes traveled among mortals under aliases Vak and Valtam.

"Wotan's Day" or "Woden's Day", has become Wednesday in English (compare Danish and Swedish onsdag). Odin's son Thor gives his name to "Thor's Day", Thursday, and his wife Frigg to Friday.

It was common, particularly among the Cimbri, to sacrifice a prisoner to Odin prior to or after a battle. One such prisoner, the "Tollund Man", was discovered hanged, naked along with many others, some of whom were wounded, in Central Jutland. The victim singled out for such a sacrifice was usually the first prisoner captured in battle. The rites particular to Odin were sacrifice by hanging, as in the case of Tollund Man; impalement upon a spear; and burning. The Orkneyinga saga relates another (and uncommon) form of Odinic sacrifice, wherein the captured Ella is slaughtered by the carving out of a "blood-eagle" upon his back.

More significantly, however, it has been argued that the killing of a combatant in battle was to give a sacrificial offering to Odin.

Sacrifices were probably also made to Odin at the beginning of summer, since Ynglinga[?] states one of the great festivities of the calendar is at sumri, þat var sigrblót "in summer, for victory"; Odin is consistently referred to throughout the Norse mythos as the bringer of victory. The fickleness of Odin in battle was also well-documented, and in Lokasenna, Loki taunts Odin for his inconsistency.

The Norsemen gave Odin many nicknames; this was in the Norse bardic tradition of kennings, a poetic method where a person, a place or an object was referred to indirectly, almost like a riddle. A list of these follows:

The legend/myth of Odin might have been based on an ancient king. This was one of the last of Thor Heyerdahl's archeo-anthropolylogical theories. See The search for Odin.

Some scholars believe that Snorri Sturlusson's version of Norse mythology is an attempt to shoehorn a somewhat more shamanistic tradition into a Greek mythological cast, although this view does a considerable disservice to Sturlusson's efforts to maintain in permanent form what was essentially an oral tradition. Sturlusson's writing (particularly in Heimskringla) tries to maintain an essentially scholastic neutrality, even though he was writing in what had by that time become an essentially Christian society. Odin is supposed to match Zeus in this scenario.